Motorized conveyor rollers of this kind are used for various purposes. A key application of such motorized conveyor rollers is larger and smaller logistics units or conveyor devices, in which such motorized conveyor rollers are used as elements of conveyor systems in combination with idle rollers or driven rollers, which are driven and set in rotation by the motorized conveyor roller via chains, belts, or the like. The rollers are arranged in sequence and form a conveyor line. In the sense of this invention, a motorized conveyor roller is also understood to mean a so-called drum motor, which, for example, serves as a drive element for belt conveyors and, therefore, has a higher performance class, optionally an internal cooling by a fluid, and a higher load level of the transmission than motorized conveyor rollers for roller conveyor lines.
Motorized conveyor rollers basically consist of an electric drive motor in the interior of a conveyor roller tube, which sets the conveyor roller tube in rotation with respect to an axle. The axle is typically held stationarily in a torque-proof manner in a frame and can be formed by two individual axle stubs at both ends of the conveyor roller or by a continuous axle body, which can also be made of several parts.
Motorized conveyor rollers are products that are subjected to varying high demands. A very quiet running is required in order to keep the noise level low in conveyor devices, which typically comprise a plurality of such motorized conveyor rollers. A cost-effective production method is also required, as these are products that are used in large quantities. Another requirement is for motorized conveyor rollers to be available in different variants. Different applications also require motorized conveyor rollers with different conveyor roller tube lengths in order to fit specific product dimensions or conveying capacities in each case. Varying requirements in terms of velocity or conveying speed and in terms of torque are also posed on motorized conveyor rollers.
Motorized conveyor rollers are, therefore, constructed for different purposes. Conveyor rollers that have a high performance and a long length in order to be able to transfer a torque corresponding to the length are known. Also known are conveyor rollers that have a high velocity in order to achieve high conveying speeds. In principle, a user of such conveyor rollers can thus select and use the conveyor roller suitable for said user. In principle, motorized conveyor rollers can be equipped with a direct drive, in which the torque generated by the electric motor and the motor velocity act directly between one or both axle units and the conveyor roller tube. However, motorized conveyor rollers having a single- or multi-stage transmission or several transmissions connected in series as gear stages are mainly used in addition to these transmission-less conveyor rollers. In these transmission-equipped conveyor rollers, a torque transfer to the transmission input shaft and from the transmission output shaft is required, and the torque on the transmission housing must be supported. To this end, various ways of supporting and transferring torque can be considered. In principle, support can be provided and torque transferred on one or both axle units, on the electric motor and on the conveyor roller tube. For example, the rotor of the electric motor can be coupled to the transmission input shaft, the transmission output shaft can be coupled to the conveyor roller tube, the transmission housing and the stator can be coupled to one axle unit, to a corresponding axle unit in each case or to both axle units, and the transmission housing and the stator can also be coupled to each other. An internal rotor or an external rotor can be used as a rotor. A spur gear transmission, planetary gear transmission, or other gearing system designs can be used as a transmission.
This possibility of choices, although desired, is nevertheless associated with numerous disadvantages. For one thing, conveyor rollers often cannot be interchanged, either in terms of geometric dimensions or in terms of performance data. This makes it difficult to replace conveyor rollers in the event of a defect and, in applications in which a quick replacement is necessary, it leads to greater effort and expenses for the user or for a replacement parts dealer in terms of stocking. Furthermore, the design of the conveyor rollers adapted to the respective requirements requires maintaining extensive stocks of the individual components that are installed in such conveyor rollers. Lastly, the method of constructing conveyor rollers is complicated and an adaptation to changing requirements is often only possible with a great amount of effort, if at all.